Question

 (2010年南通二模)—Sorry indeed，I________to your birthday party if...

—Forget it.I know you were out on business.

A．must come                          B．would come

C．must have come                   D．would have come

Answer 1

解析：选D。考查虚拟语气。此处表示对过去的虚拟，if后面省略了过去完成时(补充完整应该是if I had not been out on business)，所以主句中应该用should/would/could/might have done结构，因此选D项。